The present inventive concept relates to a semiconductor memory device, and more particularly, to a semiconductor memory device for compensating for an operating voltage difference between a near cell and a far cell in consideration of a cell position, and a memory card and memory system including the same.
Semiconductor memory devices, as illustrated in FIG. 1, usually write a signal transmitted through a metal A to memory cells in a semiconductor memory B and read data from each memory cell through the metal A. For those operations, the metal A and the semiconductor memory B are connected to each other in a bridge shape. A portion where the metal A is connected with the semiconductor memory B is referred to as a strapping node A′.
A plurality of memory cells may exist between strapping nodes A′. FIG. 1 illustrates a case where 32 memory cells exist between the strapping nodes A′. Each memory cell has a different operating voltage according to a distance from either of the strapping nodes A′. In other words, the farther a memory cell is apart from a strapping node A′, the greater operating voltage the memory cell has. Cells close to the strapping node A′ are referred to as near cells and cells far from the strapping node A′ are referred to as far cells.
There is a need for compensation of an operating voltage difference (hereinafter, refer to as “near-far compensation”).